The incident happened in the western city of Amagasaki, Japan.
After confessing that a contractor misplaced a USB drive with the personal information of 4,60,000 residents after a night out, a Japanese city has been left with more than just a headache, CBS News reported.
In the western city of Amagasaki, Japan, a private contractor whose identity has not been released carried memory sticks in a bag when he went out for drinks after work on Thursday.
But on Tuesday night, while he was working with a local pandemic relief initiative, he realised he has lost his bag.
According to CBS News, an Amagasaki official told reporters: "We deeply regret that we have profoundly harmed the public's trust in the administration of the city."
To make it easier for the data to be sent to a contact centre in the neighbouring city of Osaka, it was copied onto the USB. It had all of the city's citizens' names, gender, addresses, birthdays and other personal information, along with some individuals' tax and bank account information, the city administration said.
However, there may be some good news because the city claims the data was encrypted and the USB was password-locked. According to local media reports, there are no indications that the data has been accessed. Police have been informed of the loss and are looking into it.
"We will thoroughly ensure security management when handling electronic data," Kyodo News reported citing the city administration. "We will work to regain our residents' trust by heightening awareness of the importance of protecting personal information."
According to a travel website, Osaka Info, Amagasaki in Japan is regarded as the area's "hotspot" for nightlife.
Because there are so many izakayas (Japanese gastropubs), socialising with friends and coworkers over food and drink is the norm, the website says.